PX domain Information & PX domain Links at HealthHaven.com

	PX domain of NADH oxidase (p40phox), lipid-bound
Identifiers
Symbol	PX
Pfam	PF00787
InterPro	IPR001683
SMART	PX
PROSITE	PDOC50195
SCOP	1h6h
OPM family	60
OPM protein	1xte
Available PDB structures:
1o7kC:4-121 1gd5A:4-121 1kq6A:4-121 1h6hA:18-136 1xtnA:11-120 1xteA:11-120 2cskA:27-149 1ocsA:33-158 1ocuA:33-158 1kmdA:8-121 2ettA:4-108

The PX domain is a phosphoinositide-binding structural domain involved in targeting of proteins to cell membranes.

This domain was first found in P40phox and p47phox domains of NADPH oxidase (phox stands for phagocytic oxidase).^[1]^[2] It was also identified in many other proteins involved in membrane trafficking, including nexins, Phospholipase D, and phosphoinositide-3-kinases.

The PX domain is structurally conserved in eukaryotes, although amino acid sequences show little similarity.^[3] PX domains interact primarily with PtdIns(3)P lipids.^[4]^[5] However some of them bind to phosphatidic acid, PtdIns(3,4)P2, PtdIns(3,5)P2, PtdIns(4,5)P2, and PtdIns(3,4,5)P3. The PX-domain can also interact with other domains and proteins.

[edit] Human proteins containing this domain

Sorting nexins contain this domain. Other examples include:

HS1BP3
KIF16B (SNX23)
NCF1; NCF1C; NCF4; NISCH
PIK3C2A; PIK3C2B; PIK3C2G; PLD1; PLD2; PXK
RPS6KC1
SGK3; SH3PXD2A; SNAG1

[edit] References

^ Ponting CP (November 1996). "Novel domains in NADPH oxidase subunits, sorting nexins, and PtdIns 3-kinases: binding partners of SH3 domains?". Protein Sci. 5 (11): 2353–7. doi:10.1002/pro.5560051122. PMID 8931154.
^ Wishart MJ, Taylor GS, Dixon JE (June 2001). "Phoxy lipids: revealing PX domains as phosphoinositide binding modules". Cell 105 (7): 817–20. doi:10.1016/S0092-8674(01)00414-7. PMID 11439176.
^ Hiroaki H, Ago T, Ito T, Sumimoto H, Kohda D (June 2001). "Solution structure of the PX domain, a target of the SH3 domain". Nat. Struct. Biol. 8 (6): 526–30. doi:10.1038/88591. PMID 11373621.
^ Karathanassis D, Stahelin RV, Bravo J, Perisic O, Pacold CM, Cho W, Williams RL (October 2002). "Binding of the PX domain of p47(phox) to phosphatidylinositol 3,4-bisphosphate and phosphatidic acid is masked by an intramolecular interaction". EMBO J. 21 (19): 5057–68. doi:10.1093/emboj/cdf519. PMID 12356722.
^ Ago T, Kuribayashi F, Hiroaki H, Takeya R, Ito T, Kohda D, Sumimoto H (April 2003). "Phosphorylation of p47phox directs phox homology domain from SH3 domain toward phosphoinositides, leading to phagocyte NADPH oxidase activation". Proc. Natl. Acad. Sci. U.S.A. 100 (8): 4474–9. doi:10.1073/pnas.0735712100. PMID 12672956.

[pmid8931154-0] Ponting CP (November 1996). "Novel domains in NADPH oxidase subunits, sorting nexins, and PtdIns 3-kinases: binding partners of SH3 domains?". Protein Sci. 5 (11): 2353–7. doi:10.1002/pro.5560051122. PMID 8931154.

[pmid11439176-1] Wishart MJ, Taylor GS, Dixon JE (June 2001). "Phoxy lipids: revealing PX domains as phosphoinositide binding modules". Cell 105 (7): 817–20. doi:10.1016/S0092-8674(01)00414-7. PMID 11439176.

[pmid11373621-2] Hiroaki H, Ago T, Ito T, Sumimoto H, Kohda D (June 2001). "Solution structure of the PX domain, a target of the SH3 domain". Nat. Struct. Biol. 8 (6): 526–30. doi:10.1038/88591. PMID 11373621.

[pmid12356722-3] Karathanassis D, Stahelin RV, Bravo J, Perisic O, Pacold CM, Cho W, Williams RL (October 2002). "Binding of the PX domain of p47(phox) to phosphatidylinositol 3,4-bisphosphate and phosphatidic acid is masked by an intramolecular interaction". EMBO J. 21 (19): 5057–68. doi:10.1093/emboj/cdf519. PMID 12356722.

[pmid12672956-4] Ago T, Kuribayashi F, Hiroaki H, Takeya R, Ito T, Kohda D, Sumimoto H (April 2003). "Phosphorylation of p47phox directs phox homology domain from SH3 domain toward phosphoinositides, leading to phagocyte NADPH oxidase activation". Proc. Natl. Acad. Sci. U.S.A. 100 (8): 4474–9. doi:10.1073/pnas.0735712100. PMID 12672956.

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